Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932809Ab0BHAH4 (ORCPT ); Sun, 7 Feb 2010 19:07:56 -0500 Received: from ozlabs.org ([203.10.76.45]:33650 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755997Ab0BHAHy (ORCPT ); Sun, 7 Feb 2010 19:07:54 -0500 From: Michael Neuling To: Andrew Morton , Linus Torvalds cc: Alexander Viro , Oleg Nesterov , James Morris , Ingo Molnar , linux-fsdevel@vger.kernel.org, Anton Blanchard , stable@kernel.org, linux-kernel@vger.kernel.org, linuxppc-dev@ozlabs.org, Serge Hallyn , WANG Cong , Paul Mackerras , benh@kernel.crashing.org, miltonm@bga.com, aeb@cwi.nl Subject: [PATCH] Restrict stack space reservation to rlimit In-reply-to: <10125.1265451732@neuling.org> References: <3984.1265416993@neuling.org> <20100206042038.GB32246@kryten> <10125.1265451732@neuling.org> Comments: In-reply-to Michael Neuling message dated "Sat, 06 Feb 2010 21:22:12 +1100." X-Mailer: MH-E 8.2; nmh 1.3; GNU Emacs 23.1.1 Date: Mon, 08 Feb 2010 11:07:52 +1100 Message-ID: <18033.1265587672@neuling.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1752 Lines: 55 apkm, linus: this or something like it needs to go into 2.6.33 (& 32) to fix 'ulimit -s'. Mikey [PATCH] Restrict stack space reservation to rlimit When reserving stack space for a new process, make sure we're not attempting to allocate more than rlimit allows. Also, reserve the same stack size independent of page size. This fixes a bug unmasked by fc63cf237078c86214abcb2ee9926d8ad289da9b Signed-off-by: Michael Neuling Cc: Anton Blanchard Cc: stable@kernel.org --- fs/exec.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) Index: clone1/fs/exec.c =================================================================== --- clone1.orig/fs/exec.c +++ clone1/fs/exec.c @@ -554,7 +554,7 @@ static int shift_arg_pages(struct vm_are return 0; } -#define EXTRA_STACK_VM_PAGES 20 /* random */ +#define EXTRA_STACK_VM_SIZE 81920UL /* randomly 20 4K pages */ /* * Finalizes the stack vm_area_struct. The flags and permissions are updated, @@ -627,10 +627,13 @@ int setup_arg_pages(struct linux_binprm goto out_unlock; } + stack_base = min(EXTRA_STACK_VM_SIZE, + current->signal->rlim[RLIMIT_STACK].rlim_cur) - + PAGE_SIZE; #ifdef CONFIG_STACK_GROWSUP - stack_base = vma->vm_end + EXTRA_STACK_VM_PAGES * PAGE_SIZE; + stack_base = vma->vm_end + stack_base; #else - stack_base = vma->vm_start - EXTRA_STACK_VM_PAGES * PAGE_SIZE; + stack_base = vma->vm_start - stack_base; #endif ret = expand_stack(vma, stack_base); if (ret) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/